Intraocular Lens Implantation during Early Childhood

Authors: Lambert SR, Aakalu VK, Hutchinson AK, Pineles SL, Galvin JA, Heidary G, Binenbaum G, VanderVeen DK.

Geographical coverage: Not reported

Sector: Cataract surgery

Sub-sector: Intraocular lens

Equity focus: Not reported

Study population: Patients with cataract

Review type: Effectiveness review

Quantitative synthesis method: Narrative synthesis

Qualitative synthesis method: Not applicable

Background:

Intraocular lens (IOL) implantation in early childhood is a crucial yet challenging aspect of visual rehabilitation after paediatric cataract surgery. Traditionally, aphakic correction with contact lenses or spectacles has been the standard for infants and very young children. However, IOL implantation is increasingly being used despite concerns about long-term outcomes. While IOLs are the preferred method of optical correction for adults and older children, their use in infants and toddlers remains debated due to risks such as visual axis opacification, glaucoma, and unpredictable ocular growth leading to significant refractive errors. These issues may necessitate further interventions. The lack of FDA approval for paediatric IOLs and the need for highly skilled surgeons further complicate decision-making for this age group.

Objective:

To compare visual outcomes and adverse events associated with optical correction using an IOL versus contact lenses or spectacles after cataract surgery in children aged 2 years or younger.

Main findings:

The review included 14 studies, of which eight were rated level 1 evidence and six were rated level 2. The findings revealed that, among children with either bilateral or unilateral cataracts, IOL implantation produced visual outcomes comparable to those achieved with contact lenses or spectacles. However, IOLs were associated with an increased risk of visual axis opacities compared to aphakic correction. All treatment modalities (IOLs, contact lenses, spectacles) showed a similar incidence of glaucoma.

Ocular growth patterns were comparable across all treatment groups. Notably, infants under six months of age who received IOLs experienced a significant myopic shift, often resulting in high myopia or severe anisometropia by later childhood. Additionally, eyes with an IOL had lower corneal endothelial cell counts than aphakic eyes, while the incidence of strabismus was similar regardless of the type of visual correction. Based on current evidence, primary IOL implantation is not recommended for children six months old or younger due to a substantially higher risk of visual axis opacification compared to managing aphakia with contacts or glasses. For children older than six months, IOL placement appears to be relatively safe and its side effects are manageable; however, unpredictable eye growth often leads to large refractive errors during childhood, which may necessitate an IOL exchange or strong supplementary vision correction (such as spectacles or contact lenses).

Methodology:

Searches were conducted in PubMed, the Cochrane Library, and clinical trial databases in February 2019, without date or language restrictions. Studies were included if they had at least 40 patients, a minimum follow-up of one year, and evaluated adverse events associated with primary IOL implantation in children two years of age or younger. The strength of evidence was assessed using the rating scale developed by the Oxford Centre for Evidence-Based Medicine (British CEBM).

Applicability/external validity:

The review acknowledged variations in surgical techniques, surgeon experience, and patient demographics across the included studies. It noted that outcomes might differ in real-world clinical settings due to factors such as co-morbid ocular conditions or non-standardised postoperative care. The authors cautioned that recommendations supporting IOL use in infants older than six months assume the availability of experienced surgeons and careful case selection—factors which may not be present in all settings—thus limiting the external applicability of these conclusions in low-resource settings or for less experienced surgical teams. The review also emphasised the need for further research to develop improved surgical techniques, better lens designs, and adjuvant therapies aimed at reducing the incidence of visual axis opacities and ametropia following IOL implantation in early childhood.

Geographic focus:

No geographical limits were applied to the search. However, the review did not report the geographical distribution of the included studies, making it unclear whether the evidence is drawn from a broad international sample or concentrated in certain regions.

Summary of quality assessment:

Overall, the confidence in this review’s conclusions is low. The literature search was comprehensive, spanning multiple databases with no date or language limitations. Inclusion and exclusion criteria were clearly defined, and a list of included studies was provided. The review’s findings were detailed and accompanied by a transparent appraisal of evidence strength. However, it did not specify how many reviewers independently performed study screening and data extraction, nor did it mention whether the reference lists of included studies were checked for additional sources. Additionally, the authors did not provide a list of excluded studies or explicitly report any risk-of-bias assessment for the included studies. These omissions suggest caution in interpreting the results, as potential biases or missed studies could affect the conclusions.